JP7260016B2 - Laminated coil parts - Google Patents

Description

The present invention relates to a laminated coil component.

2. Description of the Related Art With the recent increase in communication speed and miniaturization of electrical equipment, multilayer inductors are required to have sufficient high-frequency characteristics in a high-frequency band (for example, a GHz band of 50 GHz or higher).
As a laminated coil component, for example, Patent Document 1 discloses a laminated inductor in which the lamination direction of insulating members and the axial direction of the coil are parallel to the mounting surface.

JP-A-9-129447

In the laminated inductor disclosed in Patent Document 1, the external electrodes are formed by means of sputtering, vacuum deposition, or the like on both ends of the laminated body. However, the multilayer inductor described in Patent Document 1 may not have sufficient high-frequency characteristics in the GHz band of 50 GHz or higher.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a multilayer coil component having excellent high-frequency characteristics.

A laminated coil component of the present invention is composed of a plurality of insulating layers laminated in the length direction, a laminated body containing a coil therein, a first external electrode electrically connected to the coil, and a first electrode. 2 external electrodes, wherein the coil is formed by electrically connecting a plurality of coil conductors laminated in the longitudinal direction together with the insulating layer, and the laminates face each other in the longitudinal direction. A first end surface and a second end surface, a first main surface and a second main surface facing each other in a height direction perpendicular to the length direction, and a width perpendicular to the length direction and the height direction a first side surface and a second side surface opposite in direction, the first external electrode covering at least a portion of the first end surface, and the second external electrode covering the second end surface; The stacking direction of the stack and the coil axial direction of the coil are parallel to the first main surface, and the distance between the coil conductors adjacent to each other in the stacking direction is 4 μm or more and 8 μm or less, the coil conductor has a line portion and a land portion arranged at an end portion of the line portion, and the land portions of the coil conductors adjacent to each other in the stacking direction are: They are connected to each other via via conductors, the line portion has a width of 30 μm or more and 50 μm or less, and the inner diameter of the coil conductor is 50 μm or more and 100 μm or less.

According to the present invention, it is possible to provide a laminated coil component having excellent high frequency characteristics.

FIG. 1 is a perspective view schematically showing an example of the laminated coil component of the present invention. 2(a) is a side view of the laminated coil component shown in FIG. 1, FIG. 2(b) is a front view of the laminated coil component shown in FIG. 1, and FIG. 1 is a bottom view of the laminated coil component shown in FIG. FIG. 3 is a cross-sectional view schematically showing an example of the laminated coil component of the present invention. FIG. 4 is an exploded perspective view schematically showing insulating layers forming the laminated coil component shown in FIG. FIG. 5 is an exploded schematic plan view schematically showing the state of the insulating layers forming the laminated coil component shown in FIG. FIG. 6 is a plan view schematically showing repeated shapes of coil conductors. FIG. 7 is a perspective view schematically showing another example of the laminated coil component of the present invention. 8A is a side view of the laminated coil component shown in FIG. 7, FIG. 8B is a front view of the laminated coil component shown in FIG. 7, and FIG. 7 is a bottom view of the laminated coil component shown in 7. FIG. FIG. 9 is a diagram schematically showing a method of measuring the transmission coefficient S21. FIG. 10 is a graph showing the transmission coefficients S21 of samples 1-5. FIG. 11 is a graph showing the transmission coefficients S21 of samples 6-10. FIG. 12 is a graph showing the transmission coefficients S21 of samples 11-15. 13 is a graph showing the transmission coefficient S21 of samples 3 and 16. FIG.

The laminated coil component of the present invention will be described below.
However, the present invention is not limited to the following embodiments, and can be appropriately modified and applied without changing the gist of the present invention. Combinations of two or more of the individual desirable configurations described below are also part of the present invention.

FIG. 1 is a perspective view schematically showing an example of the laminated coil component of the present invention.
2(a) is a side view of the laminated coil component shown in FIG. 1, FIG. 2(b) is a front view of the laminated coil component shown in FIG. 1, and FIG. 1 is a bottom view of the laminated coil component shown in FIG.

The laminated coil component 1 shown in FIGS. 1, 2(a), 2(b) and 2(c) includes a laminate 10, a first external electrode 21 and a second external electrode 22. there is The laminate 10 has a substantially rectangular parallelepiped shape with six faces. Although the structure of the laminated body 10 will be described later, a plurality of insulating layers are laminated in the longitudinal direction, and a coil is incorporated therein. The first external electrode 21 and the second external electrode 22 are each electrically connected to the coil.

In the laminated coil component and laminated body of the present invention, the length direction, height direction and width direction are defined as x direction, y direction and z direction in FIG. Here, the length direction (x direction), height direction (y direction), and width direction (z direction) are orthogonal to each other.

As shown in FIGS. 1, 2(a), 2(b) and 2(c), the laminate 10 has a first end surface 11 and a second end surface facing each other in the length direction (x direction). 12, a first main surface 13 and a second main surface 14 facing each other in the height direction (y direction) orthogonal to the length direction, and a width direction (z direction) orthogonal to the length direction and the height direction. It has a first side 15 and a second side 16 facing each other.

Although not shown in FIG. 1, the laminate 10 preferably has rounded corners and ridges. A corner is a portion where three surfaces of the laminate intersect, and a ridge is a portion where two surfaces of the laminate intersect.

As shown in FIGS. 1, 2(a), 2(b) and 2(c), the first external electrode 21 covers the entire first end face 11 of the laminate 10 and extending from one end face 11 to cover a portion of the first major surface 13, a portion of the second major surface 14, a portion of the first side surface 15, and a portion of the second side surface 16; there is
The second external electrode 22 covers the entire second end surface 12 of the laminate 10 and extends from the second end surface 12 to form part of the first principal surface 13 and the second principal surface 14 . , part of the first side 15 and part of the second side 16 .

Since the first external electrodes 21 and the second external electrodes 22 are arranged as described above, when the multilayer coil component 1 is mounted on a substrate, the first main surface 13 of the multilayer body 10, Any one of the second main surface 14, the first side surface 15, and the second side surface 16 serves as a mounting surface.

Although the size of the laminated coil component of the present invention is not particularly limited, it is preferably 0603 size.

When the laminated coil component of the present invention has a size of 0603, the length of the laminate (the length indicated by the double arrow _L1 in FIG. 2(a)) is preferably 0.63 mm or less. It is preferably 0.57 mm or more, more preferably 0.60 mm (600 μm) or less, and more preferably 0.56 mm (560 μm) or more.
When the laminated coil component of the present invention is 0603 size, the width of the laminated body (length indicated by double arrow _W1 in FIG. 2(c)) is preferably 0.33 mm or less, and 0.33 mm or less. It is preferably 27 mm or more.
When the laminated coil component of the present invention is 0603 size, the height of the laminated body (the length indicated by the double arrow _T1 in FIG. 2(b)) is preferably 0.33 mm or less. 0.27 mm or more is preferred.

When the laminated coil component of the present invention is 0603 size, the length of the laminated coil component (the length indicated by the double arrow _L2 in FIG. 2(a)) is preferably 0.63 mm or less. , 0.57 mm or more.
When the laminated coil component of the present invention is 0603 size, the width of the laminated coil component (the length indicated by the double arrow _W2 in FIG. 2(c)) is preferably 0.33 mm or less. It is preferably 0.27 mm or more.
When the laminated coil component of the present invention is 0603 size, the height of the laminated coil component (the length indicated by the double arrow _T2 in FIG. 2(b)) is preferably 0.33 mm or less. , 0.27 mm or more.

When the laminated coil component of the present invention is 0603 size, the length of the first external electrode covering the first main surface of the laminated body (the length indicated by the double arrow _E1 in FIG. 2(c) is preferably 0.12 mm or more and 0.22 mm or less. Similarly, the length of the portion of the second external electrode covering the first main surface of the laminate is preferably 0.12 mm or more and 0.22 mm or less.
In addition, when the length of the first external electrode in the portion covering the first main surface of the laminate and the length of the second external electrode in the portion covering the first main surface of the laminate are not constant, The length of the longest portion is preferably within the above range.

A coil incorporated in a laminate constituting the laminated coil component of the present invention will be described.
A coil is formed by electrically connecting a plurality of coil conductors laminated in the length direction together with an insulating layer.

FIG. 3 is a cross-sectional view schematically showing an example of the laminated coil component of the present invention, and FIG. 4 is an exploded perspective view schematically showing the state of insulating layers forming the laminated coil component shown in FIG. FIG. 5 is an exploded schematic plan view schematically showing the state of insulating layers forming the laminated coil component shown in FIG. 3. FIG.
FIG. 3 schematically shows the insulating layers, the coil conductors, the connecting conductors, and the stacking direction of the laminate, and does not strictly represent the actual shapes, connections, and the like. For example, coil conductors are connected through via conductors.

As shown in FIG. 3, the laminated coil component 1 includes a laminated body 10 containing a coil formed by electrically connecting a plurality of coil conductors 32 laminated together with an insulating layer, and a coil electrically connected to the coil. It has a first external electrode 21 and a second external electrode 22 connected to.
The laminate 10 has a region in which the coil conductor is arranged and a region in which the coupling conductor 41 or the coupling conductor 42 is arranged. The stacking direction of the laminate 10 and the axial direction of the coil (the coil axis A is shown in FIG. 3) are parallel to the first main surface 13 .

The dimension _L3 of the arrangement region of the coil conductor 32 in the stacking direction is preferably 85% or more and 95% or less of the length dimension _L1 of the laminate 10, and is 90% or more and 95% or less. It is more preferable to be If the dimension _L3 of the arrangement region of the coil conductor 32 in the lamination direction is 85% or more and 95% or less of the length dimension of the laminate 10, the length of the connecting conductors occupying the laminate becomes short. As a result, the stray capacitance is reduced and the high frequency characteristics are improved.

A distance _DC between the coil conductors 32 adjacent to each other in the stacking direction of the laminate 10 is 4 μm or more and 8 μm or less. When the distance _DC between the coil conductors 32 adjacent to each other in the stacking direction of the laminate 10 is 4 μm or more and 8 μm or less, the high frequency characteristics are improved.
If the distance _DC between the coil conductors adjacent to each other in the stacking direction is less than 4 μm, the stray capacitance increases and the high frequency characteristics deteriorate. On the other hand, if the distance _DC between the coil conductors adjacent to each other in the stacking direction exceeds 8 μm, the inductance of the coil will decrease.

As shown in FIGS. 4 and 5, the laminate 10 has an insulating layer 31a, an insulating layer 31b, an insulating layer 31c, and an insulating layer 31d as the insulating layer 31 in FIG. The laminate 10 has an insulating layer 35a- ₁ , an insulating layer 35a- ₂ , an insulating layer 35a- ₃ , and an insulating layer 35a- ₄ as the insulating layer 35a in FIG. The laminate 10 has an insulating layer 35b- ₁ , an insulating layer 35b- ₂ , an insulating layer 35b- ₃ , and an insulating layer 35b- ₄ as the insulating layer 35b in FIG.

The coil 30 has a coil conductor 32a, a coil conductor 32b, a coil conductor 32c, and a coil conductor 32d as the coil conductor 32 in FIG.

The coil conductor 32a, the coil conductor 32b, the coil conductor 32c, and the coil conductor 32d are arranged on the main surfaces of the insulating layer 31a, the insulating layer 31b, the insulating layer 31c, and the insulating layer 31d, respectively.

The coil conductor 32a, the coil conductor 32b, the coil conductor 32c, and the coil conductor 32d each have a 3/4 turn length of the coil 30. As shown in FIG. That is, the number of laminations of the coil conductors for forming the three turns of the coil 30 is four. In the laminated body 10, the coil conductor 32a, the coil conductor 32b, the coil conductor 32c, and the coil conductor 32d are repeatedly laminated as one unit (three turns).

The coil conductor 32a has a line portion 36a and a land portion 37a arranged at the end of the line portion 36a. The coil conductor 32b has a line portion 36b and a land portion 37b arranged at the end of the line portion 36b. The coil conductor 32c has a line portion 36c and a land portion 37c arranged at the end of the line portion 36c. 32 d of coil conductors have the line part 36d and the land part 37d arrange|positioned at the edge part of the line part 36d.

Via conductors 33a, 33b, 33c, and 33d are arranged to pass through the insulating layer 31a, the insulating layer 31b, the insulating layer 31c, and the insulating layer 31d, respectively, in the stacking direction. there is

An insulating layer 31a with a coil conductor 32a and a via conductor 33a, an insulating layer 31b with a coil conductor 32b and a via conductor 33b, an insulating layer 31c with a coil conductor 32c and a via conductor 33c, and a coil conductor 32d and a via conductor 33d. The insulating layer 31d is repeatedly laminated as one unit (portions surrounded by dotted lines in FIGS. 4 and 5). As a result, the land portions 37a of the coil conductor 32a, the land portions 37b of the coil conductor 32b, the land portions 37c of the coil conductor 32c, and the land portions 37d of the coil conductor 32d are formed into the via conductors 33a, 33b, and 37d. 33c and via conductors 33d. That is, land portions of coil conductors adjacent to each other in the stacking direction are connected to each other through via conductors.

As described above, the solenoidal coil 30 incorporated in the laminate 10 is configured.

When viewed in plan from the stacking direction, the coil 30 composed of the coil conductor 32a, the coil conductor 32b, the coil conductor 32c, and the coil conductor 32d may have a circular shape or a polygonal shape. When the coil 30 has a polygonal shape when viewed from the stacking direction, the coil diameter of the coil 30 is the diameter of a circle equivalent to the area of the polygon. axis.

As shown in FIG. 5, the diameters of the land portion 37a, the land portion 37b, the land portion 37c, and the land portion 37d when viewed in plan from the stacking direction are the line portion 36a, the line portion 36b, the line portion 36c, And, it is preferable that the line width is larger than the line width of the line portion 36d.

When viewed from above in the stacking direction, the land portion 37a, the land portion 37b, the land portion 37c, and the land portion 37d may each have a circular shape as shown in FIG. 5, or may have a polygonal shape. good. When the land portion 37a, the land portion 37b, the land portion 37c, and the land portion 37d are polygonal when viewed in plan from the stacking direction, the diameter of the area equivalent circle of the polygon is the diameter of each land portion.

Via conductors 33p are arranged to pass through the insulating layer 35a ₁ , the insulating layer 35a ₂ , the insulating layer 35a ₃ , and the insulating layer 35a ₄ in the stacking direction. Land portions connected to via conductors 33p may be arranged on the main surfaces of the insulating layer 35a ₁ , the insulating layer 35a ₂ , the insulating layer 35a ₃ , and the insulating layer 35a ₄ .

The insulating layer _35a1 with the via conductor 33p, the insulating layer _35a2 with the via conductor 33p, the insulating layer _35a3 with the via conductor 33p, and the insulating layer _35a4 with the via conductor 33p are formed by the coil conductor 32a and the via. It is laminated so as to overlap with the insulating layer 31a with the conductor 33a. As a result, the via conductors 33 p are connected to each other to form the first connecting conductor 41 , and the first connecting conductor 41 is exposed on the first end surface 11 . As a result, the first external electrode 21 and the coil 30 are connected to each other via the first connecting conductor 41 .

The first connecting conductor 41 preferably connects the first external electrode 21 and the coil 30 in a straight line, as described above. The first coupling conductor 41 linearly connects the first external electrode 21 and the coil 30 means that the via conductors 33p constituting the first coupling conductor 41 overlap each other when viewed from the stacking direction. The via conductors 33p do not have to be arranged strictly in a straight line.

Insulating layer 35b ₁ , insulating layer 35b ₂ , insulating layer 35b ₃ , and insulating layer 35b ₄ are each provided with via conductors 33q penetrating in the stacking direction. Land portions connected to via conductors 33q may be arranged on the main surfaces of the insulating layers 35b ₁ , 35b ₂ , 35b ₃ , and 35b ₄ .

An insulating layer _35b1 with via conductors 33q, an insulating layer _35b2 with via conductors 33q, an insulating layer _35b3 with via conductors 33q, and an insulating layer _35b4 with via conductors 33q are composed of coil conductors 32d and vias. It is laminated so as to overlap with the insulating layer 31d with the conductor 33d. As a result, the via conductors 33 q are connected to each other to form the second connecting conductor 42 , and the second connecting conductor 42 is exposed on the second end surface 12 . As a result, the second external electrode 22 and the coil 30 (coil conductor 32d) are connected to each other via the second coupling conductor .

The second connecting conductor 42 preferably connects the second external electrode 22 and the coil 30 in a straight line, as described above. The fact that the second coupling conductor 42 linearly connects the second external electrode 22 and the coil 30 means that the via conductors 33q forming the second coupling conductor 42 overlap each other when viewed in plan from the stacking direction. The via conductors 33q do not have to be arranged strictly in a straight line.

In addition, when the land portion is connected to each of the via conductors 33p constituting the first connecting conductor 41 and the via conductors 33q constituting the second connecting conductor 42, the first connecting conductor 41 and the second connecting conductor The shape of the connecting conductor 42 means the shape excluding the land portion.

4 and 5 illustrate the case where the number of layers of the coil conductors for forming 3 turns of the coil 30 is 4, that is, the case where the repeated shape is a 3/4 turn shape. is not particularly limited.
For example, the number of coil conductor laminations for forming one turn of the coil may be two, that is, the repeated shape may be a 1/2 turn shape.

It is preferable that the coil conductors forming the coil overlap each other when viewed in plan from the stacking direction. Moreover, it is preferable that the shape of the coil is circular when viewed from above in the stacking direction. When the coil includes a land, the shape of the coil excluding the land (that is, the shape of the line) is the shape of the coil.
Further, when a land portion is connected to a via conductor that constitutes a connecting conductor, the shape of the connecting conductor excluding the land portion (that is, the shape of the via conductor) is the shape of the connecting conductor.

Although the coil conductor shown in FIG. 4 has a circular pattern, the coil conductor may have a polygonal shape such as a square pattern.
Also, the repeating shape of the coil conductor may be a 1/2 turn shape instead of a 3/4 turn shape.

FIG. 6 is a plan view schematically showing repeated shapes of coil conductors.
As shown in FIG. 6, the repeating shape of the coil conductor 32 is circular.
The inner diameter _Rc of the coil conductor 32 is 50 μm or more and 100 μm or less. Further, the width _Wc of the line portion forming the coil conductor 32 is 30 μm or more and 50 μm or less.

The distance between adjacent coil conductors in the stacking direction is 4 μm or more and 8 μm or more, the width of the line portion of the coil conductor is 30 μm or more and 50 μm or less, and the inner diameter of the coil conductor is 50 μm or more and 100 μm or more. Since the stray capacitance between the coil conductors adjacent to each other is reduced, the high frequency characteristics are improved, and the transmission coefficient S21 at 50 GHz can be -1.2 dB or more.
When the transmission coefficient S21 at 50 GHz of the laminated coil component is -1.2 dB or more, it can be suitably used for, for example, a bias-tee circuit in an optical communication circuit. The transmission coefficient S21 is obtained from the power ratio of the transmission signal to the input signal. The transmission coefficient S21 for each frequency is obtained using, for example, a network analyzer. Although the transmission coefficient S21 is basically a dimensionless quantity, it is usually expressed in units of dB by taking the common logarithm.

The width of the line portion is 30 μm or more and 50 μm or less, more preferably 30 μm or more and 40 μm or less. When the line width of the line portion is smaller than 30 μm, the DC resistance of the coil increases. If the line width of the line portion is larger than 50 μm, the electrostatic capacitance of the coil increases, degrading the high-frequency characteristics of the laminated coil component.
By setting the width of the line portion to 30 μm or more and 40 μm or less, the transmission coefficient S21 of the laminated coil component at 50 GHz can be −1.0 dB or more.

The inner diameter of the coil conductor is 50 μm or more and 100 μm or less, more preferably 50 μm or more and 80 μm or less.
If the inner diameter of the coil conductor is smaller than 50 μm, the inductance of the coil will decrease. If the inner diameter of the coil conductor is larger than 100 μm, the electrostatic capacity of the coil becomes large, and the high frequency characteristics of the laminated coil component deteriorate.
By setting the inner diameter of the coil conductor to 50 μm or more and 80 μm or less, the transmission coefficient S21 of the laminated coil component at 50 GHz can be −1.0 dB or more.

The distance between coil conductors adjacent in the stacking direction is 4 μm or more and 8 μm or less, preferably 5 μm or more and 7 μm or less.
By setting the distance between adjacent coil conductors in the lamination direction to 5 μm or more and 7 μm or less, the transmission coefficient S21 of the laminated coil component at 50 GHz can be −1.0 dB or more.

In the coil conductor, the outer peripheral edge of the land portion is preferably in contact with the inner peripheral edge of the line portion when viewed from above in the stacking direction. As a result, the area of the land portion located outside the outer peripheral edge of the line portion becomes sufficiently small, and the stray capacitance caused by the land portion becomes sufficiently small, so that the high frequency characteristics of the laminated coil component are further improved.

The shape of the land portion when viewed from above in the stacking direction may be circular or polygonal. When the shape of the land portion is polygonal, the diameter of the area equivalent circle of the polygon is taken as the diameter of the land portion.

Although the thickness of the coil conductor is not particularly limited, it is preferably 3 μm or more and 6 μm or less.

Although the number of layers of the coil conductor is not particularly limited, it is preferably 40 or more and 60 or less.
If the number of laminations of the coil conductor is less than 40, the stray capacitance increases and the transmission coefficient S21 decreases. On the other hand, when the number of laminations of the coil conductor exceeds 60, the DC resistance (Rdc) increases.
By setting the number of laminations of the coil conductor to 40 or more and 60 or less, the transmission coefficient S21 at 50 GHz can be improved.

In the laminated coil component of the present invention, it is preferable that the land portion is not located inside the inner peripheral edge of the line portion and partially overlaps the line portion when viewed in plan in the lamination direction.
If the land portion is located inside the inner peripheral edge of the line portion, the impedance may decrease.
Further, when viewed in plan from the lamination direction, the diameter of the land portion is preferably 1.05 times or more and 1.3 times or less the line width of the line portion.
If the diameter of the land portion is less than 1.05 times the line width of the line portion, the connection between the land portion and the via conductor may be insufficient. On the other hand, when the diameter of the land exceeds 1.3 times the line width of the line, the stray capacitance caused by the land increases, which may degrade the high-frequency characteristics.

In this specification, the distance between adjacent coil conductors in the stacking direction is the shortest distance in the stacking direction between coil conductors connected via vias. Therefore, the distance between adjacent coil conductors in the stacking direction does not necessarily match the distance between coil conductors that generate stray capacitance.

In the laminated coil component of the present invention, the mounting surface is not particularly limited, but the first main surface is preferably the mounting surface.
When the first principal surface is the mounting surface, the first external electrode extends to cover a portion of the first end surface and a portion of the first principal surface, and the second external electrode , preferably extends to cover a portion of the second end surface and a portion of the first main surface.

An example of the shape of the external electrodes when the first main surface is the mounting surface will be described with reference to FIGS. 7, 8(a), 8(b) and 8(c).
FIG. 7 is a perspective view schematically showing another example of the laminated coil component of the present invention, FIG. 8(a) is a side view of the laminated coil component shown in FIG. 7, and FIG. ) is a front view of the laminated coil component shown in FIG. 7, and FIG. 8(c) is a bottom view of the laminated coil component shown in FIG.

The multilayer coil component 2 shown in FIGS. 7, 8(a), 8(b) and 8(c) includes a multilayer body 10, a first external electrode 121 and a second external electrode 122. there is The structure of the laminated body 10 is the same as that of the laminated body 10 constituting the laminated coil component 1 shown in FIGS. 1, 2(a), 2(b) and 2(c).

The first external electrode 121 covers part of the first end surface 11 of the laminate 10 as shown in FIGS. , extending from the first end surface 11 and covering a portion of the first main surface 13 . As shown in FIG. 8(b), the first external electrode 121 covers a region of the first end surface 11 including the ridge line crossing the first main surface 13, but the first end surface 11 may extend from and cover the second major surface 14 .

In FIG. 8(b), the height of the first external electrode 121 in the portion covering the first end face 11 of the laminate 10 is constant, but the first end face 11 of the laminate 10 is partially covered. The shape of the first external electrode 121 is not particularly limited as long as it is covered. For example, on the first end surface 11 of the laminate 10, the first external electrode 121 may have a mountain-like shape that rises from the end toward the center. 8C, the length of the first external electrode 121 in the portion covering the first main surface 13 of the laminate 10 is constant, but the length of the portion covering the first main surface 13 of the laminate 10 is The shape of the first external electrode 121 is not particularly limited as long as it covers the portion. For example, on the first main surface 13 of the laminate 10, the first external electrodes 121 may have a mountain-like shape extending from the ends toward the center.

As shown in FIGS. 7 and 8(a), the first external electrode 121 further extends from the first end surface 11 and the first principal surface 13 to form part of the first side surface 15 and the second surface. may be arranged over a portion of the side surface 16 of the . In this case, as shown in FIG. 8(a), the portion of the first external electrode 121 that covers the first side surface 15 and the second side surface 16 has a ridge line portion that intersects the first end surface 11 and a second side surface. It is preferably formed obliquely with respect to the ridgeline portion that intersects with the main surface 13 of 1 . It should be noted that the first external electrode 121 does not have to cover part of the first side surface 15 and part of the second side surface 16 .

The second external electrode 122 covers part of the second end surface 12 of the laminate 10 and extends from the second end surface 12 to cover part of the first main surface 13 . . As with the first external electrode 121 , the second external electrode 122 covers a region of the second end surface 12 that includes the ridgeline portion that intersects with the first main surface 13 .
Similarly to the first external electrode 121 , the second external electrode 122 extends from the second end surface 12 to form part of the second main surface 14 , part of the first side surface 15 and part of the first side surface 15 . It may cover part of the two sides 16 .

As with the first external electrode 121 , the shape of the second external electrode 122 is not particularly limited as long as it covers part of the second end surface 12 of the laminate 10 . For example, on the second end face 12 of the laminate 10, the second external electrode 122 may have a mountain-like shape that rises from the end toward the center. Moreover, the shape of the second external electrode 122 is not particularly limited as long as it covers a part of the first main surface 13 of the laminate 10 . For example, on the first main surface 13 of the laminate 10, the second external electrodes 122 may have a mountain-like shape extending from the ends toward the center.

Similar to the first external electrode 121, the second external electrode 122 further extends from the second end surface 12 and the first major surface 13 to form part of the second major surface 14, the first side surface 15 and part of the second side 16 . In this case, the portion of the second external electrode 122 that covers the first side surface 15 and the second side surface 16 is located at the ridge line portion that crosses the second end surface 12 and the ridge line portion that crosses the first main surface 13 . It is preferably formed obliquely. The second external electrode 122 does not have to cover part of the second main surface 14 , part of the first side surface 15 and part of the second side surface 16 .

Since the first external electrodes 121 and the second external electrodes 122 are arranged as described above, when the multilayer coil component 2 is mounted on a substrate, the first main surface 13 of the multilayer body 10 is mounting surface.

The height of the portion of the first external electrode covering the first end face of the laminate (the length indicated by the double arrow _E2 in FIG. 8B) is 0.10 mm or more and 0.20 mm or less. is preferred. Similarly, the height of the second external electrode in the portion covering the second end surface of the laminate is preferably 0.10 mm or more and 0.20 mm or less. In this case, stray capacitance caused by the external electrodes can be reduced.
When the height of the first external electrode covering the first end face of the laminate and the height of the second external electrode covering the second end face of the laminate are not constant, the highest It is preferable that the height of the portion is within the above range.

The laminated coil component 2 shown in FIGS. 7, 8(a), 8(b) and 8(c) is shown in FIGS. 1, 2(a), 2(b) and 2(c). Compared to the laminated coil component 1 shown, the area where the external electrodes are provided is smaller, so the stray capacitance can be reduced and the high-frequency characteristics can be improved more than the laminated coil component 1 .

7, 8(a), 8(b), and 8(c), the first connecting conductor and the second connecting conductor are the first and second connecting conductors of the coil conductors. It is preferably connected to the portion closest to the main surface of 1 . Thereby, the height _E2 of the first external electrode 121 and the second external electrode 122 covering the first end face and the second end face can be reduced. By reducing the height _E2 , it is possible to reduce the stray capacitance between the external electrode and the coil and improve the high frequency characteristics.

[Manufacturing method of laminated coil component]
An example of the method for manufacturing the laminated coil component of the present invention will be described.

First, a ceramic green sheet, which later becomes an insulating layer, is produced. For example, first, an organic binder such as a polyvinyl butyral resin, an organic solvent such as ethanol or toluene, a dispersant, and the like are added to a ferrite material and kneaded to form a slurry. After that, a ceramic green sheet having a thickness of about 10 to 25 μm is produced by a method such as a doctor blade method.
When the thickness of the ceramic green sheet is about 10 to 25 μm, it is easy to adjust the distance between adjacent coil conductors in the lamination direction to 4 μm or more and 8 μm or less.

Examples of ferrite materials include those produced by the following method. First, oxide raw materials of iron, nickel, zinc, and copper are mixed and calcined at 800° C. for 1 hour. After that, the obtained calcined product is pulverized by a ball mill and dried to produce a Ni--Zn--Cu based ferrite material (oxide mixed powder) having an average particle size of about 2 μm.

When producing a ceramic green sheet using a ferrite material, in order to obtain a high inductance, the composition of the ferrite material should be Fe ₂ O ₃ : 40 mol% or more and 49.5 mol% or less, ZnO: 5 mol% or more and 35 mol%. CuO: 4 mol % or more and 12 mol % or less, balance: NiO and trace additives (including unavoidable impurities).

As the material of the ceramic green sheets, in addition to the magnetic material such as the ferrite material described above, for example, a non-magnetic material such as a glass ceramic material, a mixed material of a magnetic material and a non-magnetic material, or the like may be used.

Next, on the ceramic green sheet, a conductor pattern that will later become a coil conductor and a via conductor is formed. For example, first, a via hole having a diameter of 20 μm or more and 30 μm or less is formed by subjecting a ceramic green sheet to laser processing. Then, the via holes are filled with a conductive paste such as silver paste to form conductor patterns for via conductors. Furthermore, on the main surface of the ceramic green sheet, a conductive paste such as silver paste is used to print a conductor pattern for a coil conductor with a thickness of about 11 μm by a method such as screen printing. As the conductor pattern for the coil conductor, for example, a conductor pattern corresponding to the coil conductor as shown in FIGS. 4 and 5 is printed.
At this time, the shape of the conductor pattern for the coil conductor is such that the coil diameter of the obtained coil conductor is 50 μm or more and 100 μm or less, and the width of the line portion is 30 μm or more and 50 μm or less.

After that, by drying, a coil sheet having a configuration in which the conductor pattern for coil conductors and the conductor pattern for via conductors are formed on the ceramic green sheet is obtained. In the coil sheet, the conductor pattern for coil conductors and the conductor pattern for via conductors are connected to each other.

Separately from the coil sheet, a via sheet having a configuration in which conductor patterns for via conductors are formed on a ceramic green sheet is produced. The conductor pattern for via conductors of the via sheet is a conductor pattern that later becomes the via conductors that form the connecting conductors.

Next, the coil sheets are stacked in a predetermined order so that coils having coil axes parallel to the mounting surface are formed inside the stack after singulation and firing.
Further, via sheets are laminated on the upper and lower sides of the laminate of coil sheets.
The number of layers of coil sheets is preferably 40 or more and 60 or less.

Next, the laminated body of the coil sheet and the via sheet is thermally compressed to obtain a compressed body, which is then cut into a predetermined chip size to obtain individualized chips. For singulated chips, the corners and edges may be rounded, for example, by barrel polishing.

Next, the individualized chips are subjected to binder removal treatment and firing at a predetermined temperature and time to form a laminated body (fired body) having a built-in coil therein. At this time, the conductor pattern for coil conductors and the conductor pattern for via conductors become coil conductors and via conductors, respectively, after firing. The coil is formed by connecting coil conductors to each other through via conductors. Also, the stacking direction of the laminate and the coil axial direction of the coil are parallel to the mounting surface.

Next, by immersing the laminate vertically in a layer obtained by stretching a conductive paste such as silver paste to a predetermined thickness and baking it, external electrodes are formed on the five surfaces (end surfaces, both main surfaces and both surfaces) of the laminate. to form a base electrode layer.
In addition, by obliquely immersing and baking the laminate in a layer obtained by stretching a conductive paste such as silver paste to a predetermined thickness, external electrodes are formed on the four surfaces (main surface, end surface, and both sides) of the laminate. base electrode layer can be formed.

Next, a nickel coating and a tin coating having a predetermined thickness are sequentially formed on the base electrode layer by plating. As a result, external electrodes are formed.

As described above, the laminated coil component of the present invention is manufactured.

Hereinafter, examples that more specifically disclose the laminated coil component of the present invention will be shown. It should be noted that the present invention is not limited only to these examples.

[Preparation of sample]
(Sample 1)
(1) A ferrite material (calcined powder) having a predetermined composition was prepared.

(2) An organic binder (polyvinyl butyral resin) and an organic solvent (ethanol and toluene) were added to the calcined powder together with PSZ balls in a pot mill, and the mixture was thoroughly mixed and pulverized in a wet process to prepare a magnetic slurry.

(3) A plurality of ceramic green sheets having a thickness of 12 μm were produced by molding the magnetic material slurry into a sheet by a doctor blade method and stamping the sheet into a rectangular shape.

(4) A conductive paste for internal conductors containing Ag powder and an organic vehicle was prepared.

(5) Fabrication of Via Sheet A via hole was formed by irradiating a predetermined portion of the ceramic green sheet with a laser. A conductive paste was filled in the via hole to form a via conductor, and a land portion was formed by screen-printing the conductive paste in a circular shape around the via conductor.

(6) Preparation of Coil Sheet After forming via holes in predetermined locations of the ceramic green sheets and filling them with conductive paste to form via conductors, the coil conductors consisting of lands and lines are printed to obtain a coil sheet. rice field.

(7) These sheets are laminated in the order shown in FIGS. 4 and 5 so that the number of laminated coil conductors is 56, then heated and pressurized, and cut by a dicer into individual pieces for lamination. A molded body was produced.

(8) The laminate molded body was placed in a firing furnace, subjected to binder removal treatment at a temperature of 500°C in an air atmosphere, and then fired at a temperature of 900°C to prepare a laminate (fired).
The dimensions of 30 laminates thus obtained were measured with a micrometer, and the average values were found to be L=0.60 mm, W=0.30 mm, and T=0.30 mm.

(9) A conductive paste for external electrodes containing Ag powder and glass frit was poured into a coating film forming bath to form a coating film having a predetermined thickness. A portion of the laminate where the external electrode is to be formed was immersed in this coating film.

(10) After dipping, baking was performed at a temperature of about 800° C. to form base electrodes for external electrodes.

(11) Electroplating was used to sequentially form a Ni film and a Sn film on the base electrode to form an external electrode.
1, 2(a), 2(b) and 2(c), and the internal structure of the laminate as shown in FIGS. 3, 4 and 5. A laminated coil component (Sample 1) was produced.
In sample 1, the distance _Dc between the coil conductors adjacent to each other in the stacking direction was set to 4 μm, the coil inner diameter _Rc was set to 100 μm, and the width _Wc of the line portion was set to 30 μm. Also, the thickness of the coil conductor was set to 6 μm, and the dimension of the arrangement area of the coil conductor in the lamination direction was set to 93.3% of the length dimension of the laminate.

(Measurement of transmission coefficient S21)
FIG. 9 is a diagram schematically showing a method of measuring the transmission coefficient S21.
As shown in FIG. 9, a sample (laminated coil component 1) was soldered to a measuring jig 60 provided with a signal path 61 and a ground conductor 62 . The first external electrode 21 of the laminated coil component 1 is connected to the signal path 61 and the second external electrode 22 is connected to the ground conductor 62 .

Using the network analyzer 63, the power of the input signal to the sample and the power of the transmission signal were obtained, and the transmission coefficient S21 was measured by changing the frequency. One end and the other end of the signal path 61 are connected to the network analyzer 63 .
The measurement results are shown in FIG. 10, and the transmission coefficient S21 at 60 GHz is shown in Table 1, respectively. FIG. 10 is a graph showing the transmission coefficient S21 of samples produced in Examples. It should be noted that the closer the transmission coefficient S21 is to 0 dB, the smaller the loss.

(Samples 2-16)
A _{laminated coil} component ₍ Samples 2 to 16) were prepared and the transmission coefficient S21 was measured. The results are shown in Table 1, Figures 10, 11, 12 and 13.
10 is a graph showing the permeability coefficients S21 of samples 1-5, FIG. 11 is a graph showing the permeability coefficients S21 of samples 6-10, and FIG. 12 shows the permeability coefficients S21 of samples 11-15. 13 is a graph showing the transmission coefficient S21 of samples 3 and 16. FIG.
For all the samples, the ratio of the dimension of the coil conductor arrangement area in the stacking direction to the length dimension of the stack was 93.3%, the same as sample 1.
For Samples 11 to 16, the number of layers of the coil conductor and the thickness of the ceramic green sheet were changed without changing the dimensions of the coil conductor arrangement region and the thickness of the coil conductor.
Samples 3, 8 and 12 all have the same distance between adjacent coil conductors in the stacking direction, the inner diameter of the coil, and the width of the line portion.

From the results in Table 1, it was found that the laminated coil component of the present invention has a transmission coefficient S21 of -1.2 dB or more at 50 GHz, and is excellent in high frequency characteristics.
Further, the width _Wc of the line portion is set to 30 μm or more and 40 μm or less, the inner diameter _Rc of the coil is set to 50 μm or more to 80 μm or less, or the distance D _c between adjacent coil conductors in the stacking direction is set to 5 μm or more to 7 μm. It was found that the transmission coefficient S21 at 50 GHz can be made -1.0 dB or more by setting the following.
Further, from the results of sample 16, the width _Wc of the line portion was set to 30 μm or more and 40 μm or less, the inner diameter _Rc of the coil was set to 50 μm or more to 80 μm or less, and the distance D _c between adjacent coil conductors in the stacking direction was set to 5 μm or more. , 7 μm or less, the transmission coefficient S21 at 50 GHz can be further reduced.

1 Laminated coil component 10 Laminate 11 First end face 12 Second end face 13 First principal face 14 Second principal face 15 First side face 16 Second side face 21 First external electrode 22 Second face external electrode 30 coils 31, 31a, 31b, 31c, 31d, 35a, 35a ₁ , 35a ₂ , 35a ₃ , 35a ₄ , 35b, 35b ₁ , 35b ₂ , 35b ₃ , 35b ₄ insulating layers 32, 32a, 32b, 32c , 32d, 132 coil conductors 33a, 33b, 33c, 33d, 33p, 33q via conductors 36a, 36b, 36c, 36d line portions 37a, 37b, 37c, 37d land portion 41 first connecting conductor 42 second connecting conductor 60 Measurement jig 61 Signal path 62 Ground conductor 63 Network analyzer A Coil central axis D _c Distance E between adjacent coil conductors in the stacking direction ₁ Length E of the first external electrode covering the first main surface ₂ Height of the first external electrode in the portion covering the first end face L ₁ Length dimension of the laminated body L ₂ Length dimension of the laminated coil component L ₃ Dimension of the arrangement area of the coil conductor in the lamination direction R _C coil Inner diameter T ₁ Height dimension of laminated body T ₂ Height dimension of laminated coil component W ₁ Width dimension of laminated body W ₂ Width dimension of laminated coil component W Width of _C line part

Claims (10)

A laminated body formed by laminating a plurality of insulating layers in the length direction and having a built-in coil therein;
a first external electrode and a second external electrode electrically connected to the coil;
The coil is formed by electrically connecting a plurality of coil conductors laminated in the length direction together with the insulating layer,
The laminated body includes first and second end faces facing each other in the length direction, first and second main faces facing each other in a height direction orthogonal to the length direction, and a first side surface and a second side surface facing each other in a width direction orthogonal to the length direction and the height direction;
The first external electrode covers at least a portion of the first end surface,
The second external electrode covers at least a portion of the second end face,
the lamination direction of the laminate and the coil axis direction of the coil are parallel to the first main surface,
a distance between the coil conductors adjacent to each other in the stacking direction is 4 μm or more and 8 μm or less;
The coil conductor has a line portion and a land portion arranged at an end of the line portion,
the land portions of the coil conductors adjacent to each other in the stacking direction are connected to each other via via conductors,
The width of the line portion is 30 μm or more and 50 μm or less,
The inner diameter of the coil conductor is 50 μm or more,
A laminated coil component characterized by having a transmission coefficient S21 of -1.2 dB or more at 50 GHz. 2. The laminated coil component according to claim 1, wherein the transmission coefficient S21 at 50 GHz is -1.0 dB or more. 3. The laminated coil component according to claim 1, wherein the line portion has a width of 30 [mu]m or more and 40 [mu]m or less. The laminated coil component according to any one of claims 1 to 3, wherein the coil conductor has an inner diameter of 50 µm or more and 80 µm or less. The laminated coil component according to any one of claims 1 to 4, wherein the distance between the coil conductors adjacent to each other in the lamination direction is 5 µm or more and 7 µm or less. The laminated coil component according to any one of claims 1 to 5, wherein the number of laminations of the coil conductor is 40 or more and 60 or less. The laminated coil component according to any one of claims 1 to 6, wherein the laminated body has a length dimension of 560 µm or more and 600 µm or less. The laminated coil component according to any one of claims 1 to 7, wherein the dimension of the arrangement region of the coil conductor in the lamination direction is 85% or more and 95% or less of the length dimension of the laminate. The laminated coil component according to any one of claims 1 to 8, wherein the dimension of the arrangement region of the coil conductor in the lamination direction is 90% or more and 95% or less of the length dimension of the laminate. The first main surface is a mounting surface,
the first external electrode extends to cover a portion of the first end surface and a portion of the first main surface;
10. The laminated coil component according to claim 1, wherein said second external electrode extends to cover a portion of said second end surface and a portion of said first principal surface. .

Images