KR101139568B1 - Stacked spiral inductor - Google Patents

Abstract

A stacked spiral inductor is disclosed. The disclosed stacked spiral inductor is composed of two or more first sub-conductor lines, the first conductor line having a half loop shape and two or more second sub-conductor lines, and the first conductive The at least two first subs of a plurality of conductive layers in a loop form including a second conductor line having a half loop shape symmetric with a sieve line, and included in odd-numbered conductive layers among the plurality of conductive layers. Conductor lines and the at least two second subconductor lines are the at least two first subconductor lines and the at least two second subconductor lines included in even-numbered conductive layers of the plurality of conductive layers. Do not overlap with each other. The stacked spiral inductor according to the present invention has an advantage of having a high goodness and a magnetic resonance frequency.

Description

Stacked Spiral Inductors {STACKED SPIRAL INDUCTOR}

Embodiments of the present invention relate to stacked spiral inductors, and more particularly, to stacked spiral inductors having a high quality factor (Q) and a self resonance frequency (SRF).

 Spiral inductors are used in the design of various radio frequency integrated circuits (RFICs), such as low noise amplifiers, frequency mixers, and voltage controlled oscillators. However, spiral inductors generally have a larger size (area) than other devices, and researches for reducing the size of spiral inductors have been actively conducted. In particular, there is a growing interest in stacked spiral inductors having relatively small sizes and capable of generating sufficient inductance.

1 to 3 are diagrams showing an example of a structure of a conventional stacked spiral inductor.

More specifically, FIG. 1 illustrates the overall structure of a conventional stacked spiral inductor 100, and FIG. 2 illustrates a top-level conductive layer M6 constituting the conventional stacked spiral inductor 100 and a lower portion adjacent thereto. The conductive layer M5 is shown, and FIG. 3 illustrates the generation principle of parasitic capacitance in the conventional stacked spiral inductor 100.

First, referring to FIG. 1, a conventional stacked spiral inductor 100 includes a plurality of conductive layers (in FIG. 1, six conductive layers M1, M2, M3, M4, M5, and M6). An example of a conventional stacked spiral inductor 100 is shown, but the number of conductive layers can be changed).

Each conductive layer (M1, M2, M3, M4, M5, M6) is formed of a half loop (first half of the first conductor line 110 (shown in dark) and the second conductor line 120 (shown in light). It includes. In this case, the half loop of the first conductor line 110 and the half loop of the second conductor line 120 have a symmetrical shape.

Here, the first conductor line 110 is a conductor line having a relatively higher potential than the second conductor line 120, and the second conductor line 120 is less than the first conductor line. It is a conductor line having a relatively low potential. 1 to 3 illustrate the brightness of the first conductor line 110 and the second conductor line 120 differently for convenience of description, the first conductor line 110 and the second conductor line ( 120 may be a conductor of the same material.

In the conventional stacked spiral inductor 100, the current input to port 1 is circulated through each conductive layer M1, M2, M3, M4, M5, and M6 and then output to port 2. This will act as an inductor.

That is, the current input through Port 1 formed in the sixth conductive layer M6 is the first conductivity of each conductive layer M1, M2, M3, M4, M5, and M6 connected through a via. Flows through the sieve line 110 in a loop form, and then passes through the second conductor line 120 of each of the conductive layers M1, M2, M3, M4, M5, and M6 connected through the via to form a loop. After it flows, it is output to Port 2. This loop-type current flow generates inductance.

However, the conventional stacked spiral inductor 100 having the above structure has a problem in that a quality factor (Q) and a self resonance frequency (SRF) are reduced due to structural limitations.

That is, as shown in FIG. 2, the conductor lines 110 and 120 included in the conductive layers M1, M2, M3, M4, M5, and M6 constituting the conventional stacked spiral inductor 100 are predetermined. Since it has an area of, the magnitude of the current flowing into the conductor lines 110 and 120 becomes larger than the magnitude of the current flowing to the outside of the conductor lines 110 and 120. That is, current flows inwardly in the conductor lines 110 and 120. As a result, the loss (Loss) in the conductor lines 110 and 120 increases, resulting in a decrease in the degree of goodness.

In addition, as illustrated in FIG. 3, in the conventional stacked spiral inductor 100, the first conductor line 110 having a relatively high potential and the second conductor line 120 having a relatively low potential are alternated. As it is located, the first conductor line 110 and the second conductor line 120 face each other (ie, overlap up and down). Accordingly, the first conductor line 110 included in each of the conductive layers M1, M2, M3, M4, M5, and M6 (more accurately, in each of the conductive layers M1, M2, M3, M4, M5, and M6). ) And the second conductor line 120) cause parasitic capacitance, thereby reducing the magnetic resonance frequency of the stacked spiral inductor 100, thereby limiting the frequency band of the inductor.

In order to solve the problems of the prior art as described above, the present invention proposes a stacked spiral inductor having a high quality factor (Q) and a self-resonance frequency (SRF).

According to a preferred embodiment of the present invention to achieve the above object, in a stacked spiral inductor, the first conductor line consisting of two or more first sub conductor lines, having a half loop (Half Loop) And a plurality of second conductive layers in a loop form, the second conductive lines comprising two or more second sub-conductor lines and having a half loop shape that is symmetrical to the first conductor lines. The two or more first sub-conductor lines and the two or more second sub-conductor lines included in odd-numbered conductive layers of the conductive layers may be the second-conducting layers included in even-numbered conductive layers of the plurality of conductive layers. A stacked spiral inductor is provided that does not overlap with the first sub conductor lines and the two or more second sub conductor lines.

The first conductor line included in any one of the plurality of conductive layers is one of the first conductor lines included in each of the upper conductive layer and the lower conductive layer positioned adjacent to the one conductive layer. The second conductor line electrically connected to at least one of the conductive layers may be electrically connected to at least one of the second conductor lines included in each of the upper conductive layer and the lower conductive layer. .

The first conductor line included in the one conductive layer is electrically connected to at least one of the first conductor lines included in each of the adjacent upper conductive layer and the lower conductive layer through vias. The second conductor line included in the one conductive layer may be electrically connected to at least one of the second conductor lines included in each of the adjacent upper conductive layer and the lower conductive layer through vias. have.

The loop size of the odd-numbered conductive layers may be the same, the loop size of the even-numbered conductive layers may be the same, and the loop size of the odd-numbered conductive layers and the loop size of the even-numbered conductive layers may be different from each other.

Wherein said at least two first sub-conductor lines are coplanar and include at least one first inner sub-conductor line located at an inner side and at least one first outer sub-conductor line located at an outer side thereof; The one or more first inner sub-conductor lines included in one conductive layer are each electrically connected to the one or more first outer sub-conductor lines included in each of the adjacent upper or lower conductive layers; The at least one first outer subconductor line included in the at least one conductive layer is electrically connected to the at least one first inner subconductor line included in each of the adjacent upper conductive layer or lower conductive layer. Can be connected.

Wherein said at least two second subconductor lines are coplanar and include at least one second inner subconductor line located at an inner side and at least one second outer subconductor line located at an outer side thereof; The one or more second inner sub-conductor lines included in one conductive layer are each electrically connected to the one or more second outer sub-conductor lines included in each of the adjacent upper or lower conductive layers; The at least one second outer sub-conductor line included in the at least one conductive layer is electrically connected to the at least one second inner sub-conductor line included in each of the adjacent upper or lower conductive layers. Can be connected.

According to another embodiment of the present invention, a stacked spiral inductor may include a loop type including a first conductor line having a half loop shape and a second conductor line having a half loop shape symmetrical with the first conductor line. A plurality of conductive layers, wherein loops by odd-numbered conductive layers of the plurality of conductive layers overlap at least a portion of the plurality of conductive layers, and loops by even-numbered conductive layers of the plurality of conductive layers are at least partially Are overlapped with each other, and the loops by the odd-numbered conductive layers are provided with a stacked spiral inductor that does not overlap with the loop by the even-numbered conductive layers.

The stacked spiral inductor according to the present invention has an advantage of having a high goodness.

In addition, the stacked spiral inductor according to the present invention has an advantage of having a high magnetic resonance frequency.

1 to 3 are diagrams showing an example of a structure of a conventional stacked spiral inductor.
4 to 6 illustrate a structure of a stacked spiral inductor according to an embodiment of the present invention.
FIG. 7 is a view for comparing the goodness (Q) and the magnetic resonance frequency (SRF) of the stacked spiral inductor and the conventional stacked spiral inductor according to an embodiment of the present invention.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention. Like reference numerals are used for like elements in describing each drawing.

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

4 to 6 illustrate a structure of a stacked spiral inductor according to an embodiment of the present invention.

More specifically, FIG. 4 illustrates the overall structure of the stacked spiral inductor 400 according to an embodiment of the present invention. In FIG. 5, the uppermost part of the stacked spiral inductor 400 according to an embodiment of the present invention. The conductive layer M6 and the lower conductive layer M5 positioned adjacent thereto are illustrated, and FIG. 6 illustrates a generation principle of parasitic capacitance in the stacked spiral inductor 400 according to an exemplary embodiment of the present invention. .

4 to 6, a stacked spiral inductor 400 according to an embodiment of the present invention will be described in detail.

First, referring to FIG. 4, the stacked spiral inductor 400 according to an exemplary embodiment of the present invention is composed of a plurality of conductive layers. In FIG. 4, the stacked spiral inductor 400 includes six conductive layers M1, M2, M3, M4, M5, and M6, but the number of conductive layers may be two or more and five or less. It may be more than.

Here, each conductive layer M1, M2, M3, M4, M5, M6 includes a first conductor line 410 (shown in dark color) and a second conductor line 420 (shown in light color). Conductor lines 410 and 420 have a symmetric half loop shape.

4 to 6 illustrate that the first conductor line 410 and the second conductor line 420 have a rectangular half loop shape, but this is only an example, and the first conductor line 410 is illustrated. The second conductor line 420 may have a half loop shape of a circle shape, or may have a half loop shape of another polygonal shape.

The division of the first conductor line 410 and the second conductor line 420 is the same as the conventional stacked spiral inductor 100 described above. That is, the first conductor line 410 is a conductor line having a relatively high potential, and the second conductor line 420 means a conductor line having a relatively low potential. In addition, the first conductor line 410 and the second conductor line 420 may be formed of a conductor of the same material.

In addition, in order to generate a loop-shaped current flow, in the odd-numbered conductive layers M1, M3, and M5, the first conductor line 410 is on the left side, and the second conductor line 420 is on the right side, and the even number is even. In the first conductive layers M2, M34, and M6, the first conductor line 410 is on the right side, and the second conductor line 420 is on the left side, and the plurality of conductive layers M1, M2, M3, and M4 are positioned on the left side. , The first conductor line 410 included in the conductive layer of any one of M5 and M6 is at least one of the first conductor lines 410 included in each of the adjacent upper conductive layer or lower conductive layer. The second conductor line 420 electrically connected to the second conductive line 420 included in the one conductive layer is one of the second conductor lines 420 included in each of the adjacent upper conductive layer or the lower conductive layer. It may be electrically connected with at least one.

For example, the first conductor line 410 / second conductor line 420 included in the third conductive layer M3 may be the first conductor line 410 / included in the second conductive layer M2. The first conductor line 410 and the second conductor line 420 included in the second conductor line 420 and the fourth conductive layer M4 may be electrically connected to each other.

As another example, the first conductor line 410 / second conductor line 420 included in the sixth conductive layer M6 may include the first conductor line 410 included in the fifth conductive layer M5. And second electrical conductor lines 420, respectively.

In other words, the conductor lines 410 and 420 included in the top / bottom conductive layer are electrically connected to the conductor lines 410 and 420 included in one neighboring bottom / top conductive layer. The conductor lines 410 and 420 included in the other conductive layer are electrically connected to the conductor lines 410 and 420 included in the upper conductor and the lower conductor.

In this case, each of the conductor lines 410 and 420 may be electrically connected through vias as shown in FIG. 4.

In addition, according to an embodiment of the present invention, the loop sizes of the odd-numbered conductive layers M1, M3, and M5 are formed to be the same, and the loop sizes of the even-numbered conductive layers M2, M4, and M6 are equal to each other. The stacked spiral inductor 400 may be formed by forming the same and differently forming the loop sizes of the odd-numbered conductive layers M1, M3, and M5 and the loop sizes of the even-numbered conductive layers M2, M4, and M6. Can be.

In addition to the structural features described above, the stacked spiral inductor 400 according to an embodiment of the present invention improves the problems of the conventional stacked spiral inductor 100 by adding two features described below.

First, as described above with reference to FIG. 2, the first conductor lines 110 and the second conductors included in the conductive layers M1, M2, M3, M4, M5, and M6 constituting the conventional stacked spiral inductor 100. In order to improve the problem that the goodness of the inductor is reduced due to the difference in magnitude between the internal current and the external current in the conductor line 120, each conductor line in the stacked spiral inductor 400 according to an embodiment of the present invention. 410 and 420 are divided into two or more sub-conductor lines so that current flows evenly in each of the conductor lines 410 and 420 (in FIGS. 4 to 6, each conductor line 410 and 420 is divided into two sub-conductor lines). Although illustrated as being divided into conductor lines 411, 412, 421, and 422, this is only an example, and the number of sub-conductor lines may be three or more according to a design change. In this case, the two or more sub conductor lines 411, 412, 421, and 422 may be located on the same plane.

As an example, as shown in FIG. 5, the first conductor line 410 includes two first sub conductor lines 411 and 412, and the second conductor line 420 includes two second sub conductors. In the case of including the conductor lines 421 and 422, a current having the same magnitude flows through each of the sub conductor lines 411, 412, 421 and 422.

In addition, if the first conductor line 410 consists of two or more first sub-conductor lines located on the same plane, the two or more first sub-conductor lines may be positioned at one or more first inner sub-conductors. It may be divided into a sieve line and one or more first outer sub-conductor lines positioned outside, in which case the one or more first inner sub-conductor lines included in any one conductive layer may be adjacent to an upper conductive layer or One or more first outer sub-conductor lines electrically connected to one or more first outer sub-conductor lines included in each of the lower conductive layers, and one or more first outer sub-conductor lines included in any one conductive layer to be adjacent to each other. It may be electrically connected with one or more first inner subconductor lines included in each layer.

Similarly, if the second conductor line 420 consists of two or more second sub-conductor lines located on the same plane, the two or more second sub-conductor lines may be positioned at one or more second inner sub-conductors. Lines and one or more second outer subconductor lines positioned outside, in which case one or more second inner subconductor lines included in any one of the conductive layers are adjacent to the upper or lower conductive layer. One or more second outer sub-conductor lines electrically connected to one or more second outer sub-conductor lines included in each of the conductive layers, and one or more second outer sub-conductor lines included in any one conductive layer to be adjacent to each other. May be electrically connected to one or more second inner sub-conductor lines included in each.

This is to ensure that the current distribution in each conductor layer is uniform.

For example, if each of the conductor lines 410 and 420 is composed of two sub conductor lines 411, 412, 421 and 422 as shown in FIG. 4, a first layer included in any one conductive layer may be used. The inner subconductor line 411 / second inner subconductor line 421 is a first outer subconductor line 412 / second outer subconductor included in each of the neighboring upper conductive layer or the lower conductive layer. The first outer subconductor line 412 / second outer subconductor line 422, which is electrically connected to the line 422, and included in one of the conductive layers, respectively, is adjacent to each of the adjacent upper and lower conductive layers. The first inner sub-conductor line 411 and the second inner sub-conductor line 421 included in the are electrically connected to each other.

Accordingly, in the conventional stacked spiral inductor 100, the current flows into the conductor lines 110 and 120 to solve the problem of improving the goodness of the inductor.

Second, as described above with reference to FIG. 3, in the conventional stacked spiral inductor 100, the first conductor line 110 having a relatively high potential and the second conductor line 120 having a relatively low potential are alternated. As a result, the first conductor line 110 and the second conductor line 120 are overlapped up and down, thereby causing a large parasitic between the first conductor line 110 and the second conductor line 120. Capacitance is generated. In order to improve such a problem, in the stacked spiral inductor 400 according to an exemplary embodiment, the first conductor line 410 and the second conductor line included in neighboring conductive layers are provided. Position 420 so that they do not overlap one another up and down to reduce the size of the parasitic capacitance.

That is, as illustrated in FIGS. 5 and 6, when the first conductor line 410 and the second conductor line 420 included in the adjacent conductive layers are disposed not to overlap each other up and down, Each of the conductor lines 410 and 420 has a small potential difference and then faces the conductor lines 410 and 420 of the upper / lower conductive layer (the potential difference across the capacitor is reduced), so that the distance also increases. As a result (the distance between the capacitors increases), the amount of parasitic capacitance that occurs is reduced.

In other words, the first conductor line 410 (the first sub-conductor lines 411 and 412) and the second conductor line 420 included in the odd-numbered conductive layers M1, M3, and M5. First conductor line 410 (first sub-conductor lines 411, 412) in which second sub-conductor lines 421, 422 are included in even-numbered conductive layers M2, M4, M6. ) And the size of the parasitic capacitance may be reduced by arranging the conductor lines so as not to overlap each other with the second conductor line 420 (the second sub-conductor lines 421 and 422).

Accordingly, the self resonant frequency of the stacked spiral inductor 400 is increased than the self resonant frequency of the conventional stacked spiral inductor 100, thereby increasing the frequency band used for the inductor.

In this case, at least some of the first conductor lines 410 and the second conductor lines 420 included in the odd-numbered conductive layers M1, M3, and M5 overlap each other up and down, and the even-numbered conductive layers The first conductor lines 410 and the second conductor lines 420 included in the fields M2, M4, and M6 overlap at least some of the first conductive lines 410 and the second conductor lines 420, and the odd-numbered conductive layers M1, M3, and M5. The first conductor lines 410 and the second conductor lines 420 and the first conductor lines 410 and the first conductor layers 410 and the even conductor layers M2, M4, and M6 included in FIG. The two conductor lines 420 may overlap each other up and down. In this case, the number of conductors that can be laminated can be sufficiently increased.

Further, according to another embodiment of the present invention, the loop sizes of the odd-numbered conductive layers M1, M3, and M5 are formed to be the same, and the loop sizes of the even-numbered conductive layers M2, M4, and M6 are mutually equal. The same size, the loop size of the odd-numbered conductive layers (M1, M3, M5) and the loop size of the even-numbered conductive layers (M2, M4, M6) are formed different from each other to implement a stacked spiral inductor 400 Can be. In this case, the first conductor lines 410 and the second conductor lines 420 included in the odd-numbered conductive layers M1, M3, and M5 completely overlap each other, and the even-numbered conductive layers M2, The first conductor lines 410 and the second conductor lines 420 included in M4 and M6 also completely overlap.

Hereinafter, referring to FIG. 7, the goodness and the magnetic resonance frequency of the stacked spiral inductor 400 and the conventional stacked spiral inductor 100 according to an exemplary embodiment will be described.

FIG. 7 is a diagram for describing the goodness and the magnetic resonance frequency of the stacked spiral inductor 400 and the conventional stacked spiral inductor 100 according to an exemplary embodiment of the present invention.

First, referring to FIG. 7A, the inductance of the usable frequency band is the same as about 5 nH, but in the case of the self resonant frequency of which the inductance is zero, the self resonant frequency of the stacked spiral inductor 400 according to the present invention ( 11 GHz) is 2.5 times higher than the conventional magnetic resonance frequency (4.2 GHz) of the stacked spiral inductor 100.

In addition, referring to FIG. 7B, it can be seen that the goodness of the stacked spiral inductor 400 according to the present invention is higher than that of the conventional stacked spiral inductor 100.

In the present invention as described above has been described by the specific embodiments, such as specific components and limited embodiments and drawings, but this is provided to help a more general understanding of the present invention, the present invention is not limited to the above embodiments. For those skilled in the art, various modifications and variations are possible from these descriptions. Therefore, the spirit of the present invention should not be limited to the described embodiments, and all of the equivalents or equivalents of the claims as well as the claims to be described later will belong to the scope of the present invention. .

Claims (11)

In the multilayer spiral inductor,
Composed of two or more first sub-conductor lines, consisting of a first conductor line having a half loop shape and two or more second sub-conductor lines, and symmetrical with the first conductor line A plurality of loop-shaped conductive layers including a second conductor line having a half loop shape
Including,
The two or more first sub-conductor lines and the two or more second sub-conductor lines included in odd-numbered conductive layers of the plurality of conductive layers are included in even-numbered conductive layers of the plurality of conductive layers. And the two or more first sub-conductor lines and the two or more second sub-conductor lines do not overlap each other. The method of claim 1,
The first conductor line included in any one of the plurality of conductive layers is one of the first conductor lines included in each of the upper conductive layer and the lower conductive layer positioned adjacent to the one conductive layer. Is electrically connected to at least one, and the second conductor line included in the one conductive layer is electrically connected to at least one of the second conductor lines included in each of the upper conductive layer and the lower conductive layer. Stacked spiral inductors. The method of claim 2,
The first conductor line included in the one conductive layer is electrically connected to at least one of the first conductor lines included in each of the adjacent upper conductive layer and the lower conductive layer through vias. Become,
The second conductor line included in the one conductive layer is electrically connected to at least one of the second conductor lines included in each of the adjacent upper conductive layer and the lower conductive layer through vias. Stacked spiral inductors. The method of claim 1,
The loop size of the odd-numbered conductive layers is the same as each other, the loop size of the even-numbered conductive layers is the same as each other,
The loop size of the odd-numbered conductive layers and the loop size of the even-numbered conductive layers are different from each other. The method of claim 4, wherein
Wherein the at least two first sub-conductor lines are coplanar and include at least one first inner sub-conductor line located at an inner side and at least one first outer sub-conductor line located at an outer side thereof,
The one or more first inner sub-conductor lines included in any one of the plurality of conductive layers may be included in each of the upper conductive layer and the lower conductive layer adjacent to the one conductive layer. Electrically connected to each of the first outer subconductor lines,
The one or more first outer sub-conductor lines included in the one conductive layer are respectively electrically connected to the one or more first inner sub-conductor lines included in each of the adjacent upper or lower conductive layers. Stacked spiral inductor, characterized in that connected. The method of claim 4, wherein
The at least two second sub-conductor lines are coplanar and include at least one second inner sub-conductor line located at an inner side and at least one second outer sub-conductor line located at an outer side thereof,
The one or more second inner sub-conductor lines included in any one of the conductive layers may be included in each of the upper conductive layer and the lower conductive layer adjacent to the one conductive layer. Electrically connected with each of the second outer subconductor lines,
The one or more second outer subconductor lines included in the one conductive layer are respectively electrically connected to the one or more second inner subconductor lines included in each of the adjacent upper and lower conductive layers. Stacked spiral inductor, characterized in that connected. In the multilayer spiral inductor,
A plurality of loop-shaped conductive layers including a first conductor line in the form of a half loop and a second conductor line in the form of a half loop, which is symmetrical to the first conductor line.
Including,
At least a portion of the first conductor lines and the second conductor lines included in the odd-numbered conductive layers of the plurality of conductive layers overlap each other, and included in the even-numbered conductive layers of the plurality of conductive layers. The first conductor lines and the second conductor lines at least partially overlap each other,
The first conductor lines and the second conductor lines included in the odd-numbered conductive layers do not overlap with the first conductor lines and the second conductor lines included in the even-numbered conductive layers. Stacked spiral inductors. The method of claim 7, wherein
The first conductor line included in any one of the plurality of conductive layers is one of the first conductor lines included in each of the upper conductive layer and the lower conductive layer positioned adjacent to the one conductive layer. Is electrically connected to at least one, and the second conductor line included in the one conductive layer is electrically connected to at least one of the second conductor lines included in each of the upper conductive layer and the lower conductive layer. Stacked spiral inductors. According to claim 8,
The first conductor line included in the one conductive layer is electrically connected to at least one of the first conductor lines included in each of the adjacent upper conductive layer and the lower conductive layer through vias.
The second conductor line included in the one conductive layer is electrically connected to at least one of the second conductor lines included in each of the adjacent upper conductive layer and the lower conductive layer through vias. Stacked spiral inductors. The method of claim 7, wherein
The loop size of the odd-numbered conductive layers is the same as each other, the loop size of the even-numbered conductive layers is the same as each other,
The loop size of the odd-numbered conductive layers and the loop size of the even-numbered conductive layers are different from each other. The method of claim 7, wherein
The first conductor line includes two or more first sub conductor lines located on the same plane, and the second conductor line includes two or more second sub conductor lines located on the same plane,
Two or more first sub-conductor lines and two or more second sub-conductor lines included in the odd-numbered conductive layers may be two or more first sub-conductor lines and two or more second sub-conductor lines included in the even-numbered conductive layers. A stacked spiral inductor, characterized in that it does not overlap two subconductor lines.

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